The pre-morbid personality of patients with Parkinson's disease.

A review of the extensive descriptive literature suggests that many Parkinsonian patients exhibit an emotional and attitudinal inflexibility, a lack of affect and a predisposition to depressive illness, which may antecede the development of motor abnormalities by several decades. Introspective, over-controlled, anhedonic personality traits together with suppressed aggresivity are frequently found. It is unclear whether these behavioural patterns are relevant aetiological factors or prodromal symptoms of the disease.